基于配电变压器无功补偿技术的研究

Research on Reactive Power Compensation Technology Based on Distribution Transformer

配电网普遍采用的无功补偿方式分为高压集中补偿和低压分散补偿,考虑到两种补偿方式的不足,提出一种基于配电变压器的一体化静止无功补偿(STATCOM)技术。该技术通过将补偿装置接到高压绕组抽头,充分利用配电变压器的富余容量,实现对变压器和负荷的动态无功补偿,并引入虚拟三相对称系统保证检测电流的精度。通过仿真分析,验证一体化STATCOM技术可实现配电网三相不平衡状态下无功功率的动态跟踪补偿,改善变压器输出电能质量。

The reactive power compensation method commonly used in the distribution network is divided into high-voltageconcentrated compensation and low-voltage distributed compensation. Considering the shortcomings of the two compensation methods,this paper proposes a technology of integrating static reactive power compensation （STATCOM） based on distribution transformers. Thistechnology can realize the dynamic reactive power compensation of transformer and load by connecting the compensation device to thehigh-voltage winding tap and making full use of the surplus capacity of the distribution transformer. Aiming at the influence of three-phase unbalanced operation on the results of reactive current cross-port detection, the virtual three-phase symmetrical system is introduced to ensure the accuracy of current detection. At last, the simulation shows that the integrating STATCOM technology realized thedynamic tracking compensation of reactive power in the three-phase unbalanced state of the distribution network and improved theoutput power quality of the transformer.